Strain Measurement in the Left Ventricle During Systole with Deformable Image Registration

摘要

The objective of this study was to validate a deformable image registration technique, termed Hyperelastic Warping, for left ventricular strain measurement during the systole using cine-gated nontagged MRI with strains measured from tagged MRI. Tagged and non-tagged cine images were obtained on a 1.5 T Siemens Avanto clinical scanner with a TrueFISP imaging sequence. The Hyperelastic Warping solution was evolved using a series of non-tagged images in 10 phases from end-diastole to end-systole. The solution may be considered as ten separate Warping problems with multiple Templates and Targets. At each stage, an active contraction was initially applied to the FE model, and then Warping penalty forces were utilized to generate the final registration. Warping results for circumferential strain were correlated (R~2 =0.59) with results obtain from tagged MR images analyzed with a HARP algorithm. Results for fiber stretch, LV twist, and transmural strain distribution were similar to values in the literature. Hyperelastic Warping represents a novel approach for quantifying 3-D regional strains within the myocardium with a high resolution.